Need help ! Custom Fields not working on bigger amount of categorys

[neiras]

Hi, im running in to one problem with custom fields, i have many category's for all car makes & models and when i try to add custom fields to all car makes and models half of category's gets deselected them self after i just have selected them alland saved settings, it looks like im running in to some memory problem or some type of limits, as i have 11 000 categorys and i need to set custom fields for almost all of them and have no idea why its stoping me from adding them to all categorys, if i select less categorys everything works fine

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